Insulting voters can only lead to defeat – for both the Tories and Labour

Shutting out the voters might seem like a sensible strategy, but it can only lead to one result: a slap in the face come polling day.

Terrified by the fear of another Gillian Duffy moment, the parties have adopted a cautious approach to these precious few weeks that tries to avoid calamity at the expense of giving themselves a chance of actually changing the game. Elections should not be shutting-down operations, but that is the approach taken by the Conservatives and Labour.

Lynton Crosby might be placing his faith in a late incumbency swing, but there are no signs of it materialising yet. Labour stands more to gain from seeking a sudden moment where longstanding perceptions shift. As #milifandom shows, any progress they have made in this campaign isn't really of their making.

It's ironic, really. Gordon Brown's 'bigotgate' disaster helped bring down the New Labour government because by writing off Duffy, Brown was writing off millions of other voters too. Yet in strenuously trying to avoid a similar fate another mass insult is taking place: voters are being removed from the political process of the main air-war campaigns altogether.

It leaves the media left with nothing better to do than wonder what a hung parliament means. It explains the focus on the SNP, a party that can't expect to take more than four per cent of the national vote share but could end up seizing 50-odd seats – and advancing its long-term agenda of breaking up Britain. For this is a campaign overshadowed by the far more important contest of 2014, when the future of this country was at stake. That matters a lot more than who governs the UK over the next five years. But the Conservatives are prioritising power over the preservation of the union. It is ugly politics, made no easier to accept by the fact that a preoccupation with the SNP's role is exactly what the Tories hope to achieve by shutting down genuine debate elsewhere.

What this campaign shows is an abdication by both of the main two parties of any sense they can restore the old politics that served them so well in the 20th century. Those steady rotations of power worked well for Labour and the Conservatives for many decades. But their two-party system led to over-centralisation and an obsession with consistency that belied the reality of both parties. They were always broad churches characterised by struggles for influence between competing sub-parties. Now, with the ideological tensions of the 1980s subdued, those fringes have begun breaking off. Despite the desperate need for the Tories and Labour to find a way of adapting, of combating this drift to the edges that has amplified extreme voices, the 2015 campaign has shown neither really has an answer.

But adapt they must. In the digital age democracy must be about more than targeted emails and ironic hashtags. In the next parliament whichever party is in power must find ways of embracing the new expectations of voters about what British politics means. Yes, in a hung parliament that means working harder to secure consensus in the Commons. But it's about more than that – it's about persuading the general public that they aren't nearly as shut out from everyday politics as they are from the stage-managed bore-fests of this interminable campaign.